Polycrystalline tin-doped indium oxide (ITO) thin films were prepared by Pulsed Laser Deposition (PLD) with an ITO (In\(_2\)O\(_3\)-10 wt.% SnO\(_2\)) target and deposited on borosilicate glass substrates. By changing independently the thickness, the deposition temperature and the oxygen pressure, a variety of microstructures were deposited. The impact on thin film physical properties of different gas dynamics is stressed and explained. Films deposited at room temperature (RT) show poorer opto-electrical properties. The same is true for films deposited at low or high oxygen pressure. It is shown that films grown with 1 to 10 mT Oxygen pressure at 200 °C show the best compromise in terms of transmittance and resistivity. The influence of the thickness, the substrate temperature and the oxygen pressure on the microstructure and ITO film properties is discussed. A practical application (a Dye Sensitized Solar Cell) is proposed.

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This thesis is concerned primarily with the testing and analysis of design variations of the Lynch motor, which is an axial gap permanent magnet dc machine. These variants include: a standard production motor, a motor with low iron volume, a motor with bigger area of magnets and a motor using powder iron instead of laminations. The powder iron motor was constructed by the author, while all the other motors were provided by the Lynch Motor Company. Tests were conducted to evaluate motor circuit parameters, losses and efficiency using a purpose built test rig which was built in the first stage of the project. Finite element analysis (FEA) was used to determine the levels of the magnetic saturation in the different motors and calculate torque, inductance and EMF. The FEA was also used as bases for comparison with analytical electromagnetic calculations. A dynamic circuit model, whose parametric were derived from FEA and analytical calculations validated by test, was also constructed to study the effect of brush thickness on circulating current and torque production. The results of the work revealed that the larger magnet motor has a high level of saturation resulting in a higher slope of the torque-speed curve. The lower iron volume motor and the powder iron cored motor produced less torque and have less flux density than the standard Lynch motor. The test results proved that the selected powder iron material is usable in the Lynch rotated armature but it still needs improvements to close the performance gap with laminations. The powder iron motor has back emf that is 10% lower than the standard motor, and consequently a lower efficiency. The results show that performance of the Lynch motor can be improved by optimising the size of the saturated parts of the motor, which are the stator discs and the armature teeth. In addition, careful selection of brush number, geometry and type can improve the motor performance. An alternative single gap motor was also studied. The test results show that it has more armature reaction than the dual gap motor and therefore it produced less torque with less efficiency.